1. Field of the Invention
The present invention relates to a lid speculum that can be used to retract an eyelid of an eye.
2. Prior Art
Lid speculums are typically used to retract an eyelid when performing an ophthalmic procedure. For example, the eyelid is retracted when performing a phacoemulsification or LASIK procedure. Unfortunately, lid speculums of the prior art do not operate in an anatomically correct manner. Prior art speculums tend to create pressure points that cause patient discomfort.
FIGS. 1a-j show a conventional lid speculum 1 retracting an eyelid E. The lid speculum 1 has a pair of blades 2 that pivot about a pivot axis 3. In order to have the blades 2 essentially parallel when opened, the speculum is placed on the patient in a manner that creates an anatomically incorrect angle, as shown in FIGS. 1b and 1d. This results in a kinked and uncomfortable pressure point 4 in both the upper and lower eyelids.
The blades 2 maintain a constant two-dimensional plane of orientation as they are opened, pulling directly from each other, as indicated by the arrows in FIG. 1c, instead of following the contour of the globe. The blades 2 are parallel when initially open but then become oblique and create a pressure point 5 at the kinked tarsal plate. It would be desirable to provide a lid speculum that would operate in a more anatomically correct manner than speculums of the prior art.